Method of making an improved jar container

ABSTRACT

An improved jar and method of making the same. The double walled jar comprises a single piece double walled container, bottom plug, and lid. The container comprises an inner wall structure with open top and a closed bottom. A shoulder portion extends from the outer surface of the inner structure. Sets of threads are located above the shoulder portion about the outer surface of the inner structure. An outer wall structure extends from the shoulder portion, forming a gap between the structures. The terminal end of the outer structure extends past the closed bottom and has a notched channel within the inner surface of the outer structure below the closed bottom. A bottom plug having a portion shaped for a snap fit into the notched channel is used to cover the bottom of the container. A lid is used to complete the container as a jar.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The claimed invention relates to an improved jar container andmethod for making an improved jar container, and in particular a singlepiece double walled container with bottom plug.

[0003] 2. Description of the Prior Art

[0004] Double walled containers have been in use for many years and areused for many different applications such as providing insulation forcontents of the container, providing increased protection for thecontents of the container, and providing a container that isaesthetically appealing. The common practice of making a double walledcontainer is assembling two discrete piece by making an outer singlewall structure designed to accept a single wall container, and a singlewall container designed to nest into the outer wall structure. Since thedouble walled container is made of two discrete pieces, additionalmeasures are typically incorporated into the two pieces so that they arejoined as a single piece, including but not limited to elaborate meansfor preventing the rotation of one piece with respect to the other.

[0005] This type of double walled container is expensive to manufacturefor several reasons. This method is labor intensive in that the singlewall container has to be inserted into the outer single wall structure.In order to properly insert the single wall container into the outersingle wall structure, the person or apparatus has to orient one withrelationship to the other. This requires time that ultimately figuresinto the cost of producing such a double walled container. Further, theassembly of the single wall container into the outer single wallstructure is a source of breakage of both pieces, increasing theper-piece manufacturing cost. A common solution to this breakage problemis increasing the thickness of both pieces to prevent breakage, furtherincreasing the material costs involved in the product. This method isalso costly in that valuable manufacturing machine time is taken up inproducing each of these complicated pieces. Therefore, there is a needfor a double walled container that is cheaper to fabricate and assemble.

[0006] Containers of this type do not make attractive see-throughcontainer. When containers of this type are made of translucentmaterials, the structures used to join the two discrete parts togetherare visible, obstructing the view of the contents of the container,presenting an unattractive appearance. Therefore, there is a need for adouble walled see-through container that is aesthetically pleasing tothe user of the container. Further, due to the fact that double walledcontainer of this type are not made of translucent material, anylabeling or markings of the container has to be done on the outside ofthe container that is susceptible to damage during handling of thecontainer. Therefore, there is a further need for a double walledsee-through container that allows the placement of a label or markingsbetween the inner and outer wall of the container so that the label ormarkings may not be damaged during handling.

[0007] Various paper and plastic cup-type containers having double wallconstruction and base/bottom construction have been used in the past.For example, U.S. Pat. No. 2,266,828 (the '828 Patent) discloses a papercup with dual walls and a disc-shaped bottom member with an integralupwardly extending circumferential flange which seats tightly againstthe surrounding wall of the body and is secured therein by an adhesive.U.S. Pat. No. 5,542,599 (the '599 Patent) discloses a beverage cup ofbiodegradable paper elements having an inner side wall, an outer sidewall spaced exteriorly of the inner side wall, and a bottom closureadhesively secured to and forming a fluid tight closure with the bottomof the inner side wall and a rim defined by the upper margin of theinner side wall. The '828 Patent and the '599 Patent both require theproduction of two complex pieces that have to be assembled in a certainway, while having structure that is easily susceptible to breakage ordeformation during assembly.

[0008] Similar containers have also been designed out of plastic. U.S.Pat. No. 4,040,537 discloses a plastic cup of the thin wall varietyhaving inner and outer spaced walls with an insulating air spacetherebetween. The inner and outer walls of each cup are spaced apart ina stacking and sealing ring area to allow pivotal movement of an innercup wall with regard to its corresponding outer cup wall, whereby atelescoped stack of nested cups can flex. U.S. Pat. No. 4,280,640discloses an integral double-wall container, made of a syntheticplastic, for handling bulk materials. The '640 Patent also discloses amethod of making the container by rotational molding thus avoidingwelding and its attendant difficulties. The container is integral and isone-piece and is made of a synthetic plastic, preferably polyethylene.The method of making the container by rotational molding comprisesplacing the outer mold into position, placing the inner mold intoposition within the outer mold, inserting a powder of synthetic plasticinto the space between the molds, heating the powder, rotating the moldto gravity spread the melted powder, and cooling the plastic beforeremoving the molds. The disposable insulated container of U.S. Pat. No.5,775,577 comprises an inner container structure and an outer insulatingwrap that comprises a microflute laminated structure. The microflutelaminated structure has a first corrugated laminate of microflutecorrugations which extend substantially circumferentially around theside wall of the inner container and a second, outer sheet laminate ofthe thin flexible paper which presents a substantially smooth outersurface for the user's hand. These containers suffer many of thedisadvantages that were previously mentioned.

[0009] Other references include the display-type container of U.S. Pat.No. 5,791,506 that includes a panel member that is preferablytransparent, to permit viewing of the jar contents, and a screw cap thatis preferably opaque, to largely conceal its own thread, and that of aflat jar. The dual wall container of U.S. Pat. No. 5,950,917 is formedof a laminated blank wrapped about the longitudinal axis of thecontainer to define an inner sidewall and an outer sidewall. Scores areprovided within the inner sheet for forming annular air pockets betweenthe two sidewalls.

[0010] Other containers have used plug type bottoms to complete thecontainers. U.S. Pat. No. 6,173,858 discloses two-piece cups formed froma thermoformable plastics material, including a bottom wall disc whichis bonded to an inwardly turned annular bottom flange of the side wallby an upwardly and inwardly sloped transition wall. The bottom wall discmay be in the form of multiple concentrically disposed, annular bottomwall segments which are connected to one another by respective ones of aplurality of transition walls. U.S. Pat. No. 4,613,063 discloses a threepiece safety dispensing package for granular or pellet material.Introducing a snap-in plug bottom into the open container bottom sealsthe package.

[0011] Several different methods of manufacturing double walledcontainers have been used in the past, such as vacuum molding. U.S. Pat.No. 4,192,701 discloses a double wall plastic article and a method andapparatus for forming a double wall article with a pair of deformablethermoplastic sheets wherein the sheets are mounted, in face to facecontiguous relation, on a single pair of laterally spaced longitudinallyextending rails. The rail supported, contiguously disposed sheets areheated to forming temperature and are then subjected to differentialforming pressures via a pair of opposed molds which seal to the sheetsto fuze perimetrically extending, opposed portions of the sheets andform the border of the article being formed. Differential pressure isthen applied to a central portion of at least one of the sheets withinthe formed border to withdraw the central portion and form the article.

[0012] The container of U.S. Pat. No. 5,169,024 is a high pressurecontainer made by rotationally molding a first wall of plastic materialclosed at the bottom and open at the top, and a second wall of plasticmaterial also closed at the bottom and open at the top that encloses andis bonded to the first wall. The first wall is formed by a one-shotrotationally moulding process whereafter the second wall is rotationallymoulded around the inner wall.

SUMMARY OF THE INVENTION

[0013] A principal object of the claimed invention is to provide a lesscostly double walled container that can be mass produced on a highquantity production basis with new features and advantages not found inconventional double walled containers in the market place prior to ourinvention.

[0014] Accordingly, it is an object of the claimed invention to avertthe problems of the prior art. More particularly, it is an object of theinvention to provide a double walled container having a simplifiedoverall design. The claimed invention provides a single piece doublewalled container where the inner wall and the outer wall is made of onecontinuous piece, thus obviating the need for joining structures andstructures that prevent the rotation of one discrete part in relation toanother.

[0015] Another object of the invention is to provide a double walledcontainer that requires less assembly time. The claimed inventionprovides a single piece double walled container and a bottom plug thatcovers the bottom of the container. The double walled container does notrequire assembly in that it is molded out of a single piece. The bottomplug is of a simple, symmetrical design so that during the assembly ofthe bottom plug into the bottom of the container, the step of orientingthe bottom plug in relation to the container is drastically reduced. Theassembly of the bottom plug into the bottom of the container is a simplesnap-in process, eliminating the need for more complicated turn-to-lockassembly methods.

[0016] A further object of the invention is to provide a double walledcontainer that is less susceptible to breakage during assembly of thecontainer. The claimed invention provides a single piece double walledcontainer with a design that does not require interlocking structuresthat may break during assembly. The bottom plug is also designed to beless susceptible to breakage during assembly into the bottom of thecontainer.

[0017] Still a further object of the invention is to provide a doublewalled container having reduced material costs and reduced overallweight. The claimed invention provides a single piece double walledcontainer with less duplication of structure and eliminates the need forinterlocking structures. The reduction and elimination of materialnecessary to fabricate the container results in a container thatrequires less material to make the same size container using the priorart designs. This reduction in material makes the cost of material tomake the container correspondingly less and also reduces shippingcharges that may be incurred in shipping such containers.

[0018] Yet a further object of the invention is to provide an attractivetransparent double walled container. The claimed invention provides adouble walled container that when made out of a translucent material,the contents of the container can be view unobstructed. This isaccomplished by making the double walled container out of a singlepiece, thus eliminating the need for retaining structures that may beaesthetically unattractive.

[0019] An even further object of the invention is to provide a doublewalled container that can be manufactured using simplified molds. Theprior art required the construction of two complicated mold designs thatwere expensive to build and maintain. The claimed invention provides asingle piece double walled container of simplified design as previouslydescribed. This simplification in design also allows the simplificationof the mold that is used to fabricate the double walled container.Simplified mold design is important in that it reduces the overall costof constructing the mold and reduces the costs associated with moldmaintenance. This also translates into reduced piece part cost, allowingembodiments of the claimed invention to be manufactured with reducedcapital equipment costs. Similarly, the mold design of the bottom plugis greatly simplified. The prior art required a second correspondinglycomplicated piece to nest into the outer wall structure. In the claimedinvention, the second piece necessary to complete the container isreduced to a simplified disc type design. The cost of constructing themold for this design is much less than before, and also provides a moldthat is easier and less costly to maintain.

[0020] To achieve the foregoing and other objects of the claimedinvention, an improved jar container and method of making the same areprovided. The jar comprises a single piece double walled container, abottom plug, and a lid.

[0021] The single piece double walled container comprises an inner wallstructure having an open top end and a closed bottom end. An outer wallstructure having a proximal end and a terminal end encircles the innerwall structure forming a gap between the inner wall structure and theouter wall structure. The terminal end of the outer wall structureextends past the closed bottom of the inner wall structure and has anotched channel within the inner surface of the outer wall structurelocated below the closed bottom of the inner wall structure. A shoulderportion linking the inner wall structure with the outer wall structureextends continuously from and about the outer surface of the inner wallstructure to the proximal end of the outer wall structure. The shoulderportion is the sole means of linking the inner wall structure and theouter wall structure. A set of threads located above the shoulderportion and about the outer surface of the inner wall structure.

[0022] The bottom plug is sized and shaped to fit within the areaencircled by the outer wall structure and is symmetrical about its longaxis. The bottom plug has a portion sized and shaped for a snap fit intothe notched channel within the inner surface of the outer wallstructure.

[0023] The notched channel is located within the inner surface of theouter wall structure such that a face of the bottom plug comes intocontact with the closed bottom end when the bottom plug is snapped intothe notched channel, the closed bottom providing support to the bottomplug.

[0024] The thickness of the outer wall structure and the thickness ofthe bottom plug have a relationship such that the bottom plug deflectsalong the long axis of the bottom plug as the bottom plug is pushed intothe area encircled by the outer wall structure and returns to isoriginal shape when the bottom plug snaps into the notched channel.

[0025] The lid is sized and shaped to cover the open top end of theinner wall structure. The lid has a set of threads formed to fit inmating relationship with the set of threads located about the outersurface of the inner wall structure. The shoulder portion acts as afluid tight seat for the lid when the lid is secured to the container.

[0026] To further achieve the foregoing and other objects of the claimedinvention, a method of making the jar container is provided. The methodcomprises molding a single piece double walled container having an innerwall structure with a closed bottom end and an outer wall structure, theouter wall structure having a terminal end extending past the inner wallstructure and a notched channel within the inner surface of the outerwall structure. Then a bottom plug, sized and shaped to fit within thearea enclosed by the outer wall structure having a portion sized andshaped for snapping into the notched channel, is molded. Finally, thebottom plug is snapped into the notched channel of the double walledcontainer.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027]FIG. 1 is a cross sectional view of the improved jar container.

[0028]FIG. 2 is a cross sectional view of the bottom plug.

[0029]FIG. 3 is a plan view of the bottom plug.

[0030]FIG. 4 is a cross sectional view of the container and the bottomplug.

[0031]FIG. 5 is an enlarged view of the V shaped channel.

[0032]FIG. 6 is a cross sectional view illustrating the deflection ofthe bottom plug.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0033]FIG. 1 illustrates a round, double walled jar 10. The jar 10comprises a single piece double walled container 100, a symmetricalbottom plug 200 that is sized and shaped to fit into the bottom of thecontainer 100, and a lid 300 that is sized and shaped to fit over theopen end of the container 100. It is contemplated that different sizesand shapes of jar 10 will be made following the teachings of thisdetailed description.

[0034] The double walled jar 10 as shown in FIG. 1 was designed toprovide a double walled container 100 having an overall simplifieddesign. The container 100 is of a single piece design, eliminating theneed for elaborate joining structures to join the inner wall 105 to theouter wall 120. Further, the jar 10 is designed to reduce the assemblytime necessary to provide a double walled jar. The symmetrical design ofthe bottom plug 200 reduces the complexity and time involved inassembling the bottom plug 200 into the bottom of the container 100 asshown in FIGS. 2 and 6.

[0035] These simplifications in piece part designs correspondinglysimplify the mold design needed to produce the container 100 and thebottom plug 200. The simplification of these mold designs reduces theinitial cost of constructing the molds and also reduces maintenancecosts associated with maintaining the integrity of the molds. The designof the container 100 presents fewer injection mold details that aresusceptible to erosion due to the abrasive nature of the material beinginjected into the mold during the fabrication of the container 100.

[0036]FIG. 1, and 4-6 show the single piece double walled container 100comprises an inner wall structure 105, a shoulder portion 110, a set ofthreads 115 located above the shoulder portion 110, an outer wallstructure 120 extending continuously from the shoulder portion 110forming a gap 145 between the inner wall structure 105 and the outerwall structure 120, and a V shaped channel 125 within the inner surfaceof the outer wall structure 120. See FIG. 5 for an enlarged view of theV shaped channel 125. The container 100 is preferably made of apolypropylene or a polystyrene material.

[0037] The inner wall structure 105 as shown in FIGS. 1, 4 and 6illustrate a circularly configured inner wall structure 105. The innerwall structure 105 has an open top end 130 and a closed bottom end 135.The relationship between the inner walls 140 is variable depending uponthe intended use of the container 100. The inner walls 140 of the innerwall structure 105 are angled so that the distance between the innerwalls 140 near the bottom is reduced, making the opening at the open topend 130 greater in area than the closed bottom end 135. The closedbottom end 135 meets the inner walls 140 in a varying relationship,depending upon the intended use of the container 100. The inner wallstapers into the closed bottom end 135. The thicknesses of the innerwalls 140 vary within a range depending upon the manufacturingprocessing parameters and the type of material used. The targeted rangeis from about 0.035 inches to about 0.047 inches.

[0038] A shoulder portion 110 is molded into the outer surface of theinner wall structure 105 as shown in FIG. 1. The placement of theshoulder portion 110 about the outer surface may vary depending upon theintended use of the container 100. FIG. 1 shows that in this embodimentof the invention the shoulder portion 110 is located approximately ⅓ ofthe way down the inner wall structure 105, leaving space for threads 115to be placed above the shoulder portion 110. The distance that theshoulder portion 110 extends is variable depending upon the size andintended use of the container 100. In this embodiment of the invention,the shoulder portion 110 extends substantially perpendicular from thesurface of inner wall structure 105 to create a gap 145 between theinner wall structure 105 and the outer wall structure 120 of about 0.2inches. When the lid 300 is screwed onto the male threads 115, theshoulder portion acts as a fluid tight seat to prevent fluids fromescaping from the container.

[0039]FIG. 1 shows in the preferred embodiment of the invention, a setof male threads 115 are molded into the outer surface of the inner wallstructure 105 above the shoulder portion 110, protruding from thesurface of the inner wall structure 105. In other embodiments of theinvention, female threads are molded into the outer surface of the innerwall structure 105 above the shoulder portion 110, recessed from thesurface of the inner wall structure 105. In yet other embodiments of theinvention, no threads are used in the container 100.

[0040] An outer wall structure 120 is molded continuously from theshoulder portion 110, extending roughly parallel with the inner walls140 of the inner wall structure 105, creating the second wall of thedouble walled container 100 as shown in FIGS. 1 and 4-6. The thicknessof the outer wall structure 120 in the preferred embodiment is less thanthe thickness of the inner wall structure 105. See the enlarged view ofFIG. 5. FIGS. 1, 4, and 6 show that in the embodiment illustrated, theouter wall structure 120 is also configured in a circular configuration.However, it is contemplated that the configuration of the outer wallstructure 120 may vary from the configuration of the inner wallstructure 105. The terminal end 150 of the outer wall structure 120extends past the closed bottom end 135 of the inner wall structure 105and has a V shaped channel 125 within the inner surface of the outerwall structure 120 located below the closed bottom end 135 of the innerwall structure 105. See FIG. 5.

[0041] The container 100 is designed to reduce the overall cost ofmaterial to make the jar 10, and to reduce the overall weight of the jar10. Requiring less material to make a container of the same sizemanufactured using prior art designs reduces the cost of material tomake the container 100. This is accomplished by reducing the amount ofduplication of structure as well as eliminating the need for elaboratestructure to join the inner wall 105 to the outer wall 120. The outerwall 120 is contiguous to the inner wall 105 by way of the shoulderportion 110 only. See FIG. 1. This allows the jar 10 to be sold at alower price due to the decreased material cost associated with makingthe container 100.

[0042] The use of a single piece double walled container 100 allows thecontainer 100 to be fabricated out of translucent plastic so that thecontents of the container 100 can be seen from the outside of thecontainer 100 through the outer wall 120 and the inner wall 105unobstructed. FIG. 1 illustrates that there is no structure obstructingthe view of the contents of the container through the outer wall 120 andthe inner wall 105. This aspect of the claimed invention is an importantdifference from the prior art that was previously discussed. The priorart double wall containers typically use two discrete containers innested relationship. Manufactures of this type employ various types ofstructures to fasten the inner container to the outer container. If thistype of container were fabricated out of a translucent material, thestructures used to fasten the inner container to the outer containerwould obstruct the viewing of the contents of the container. With thisin mind, the claimed invention makes it possible to produce atranslucent double walled container that is more aesthetically appealingto the viewer of the container.

[0043] Due the problems of the prior art previously mentioned, themarking or labeling of the container 100 was typically accomplished byprinting markings directly on the outer face of the outer wall 120 ofthe container 100 or adhering labels to the outer face of the outer wall120 of the container 100. This method of marking or labeling prior artcontainers was expensive due to the cost of printing directly onto acurved surface, or using adhesive backed labels. As a further drawback,both of these methods require the alignment of the markings or labelwith the container 100 so that the marking or label is correctlyoriented with the container 100.

[0044] With these further problems of the prior art in mind, a furtherfeature of molding the container 100 out of a translucent material isthe placement of a label or labels 155 between the inner wall 105 andthe outer wall 120, decreasing the cost in placing markings on thecontainer. See FIG. 1. The reduction in cost is accomplished due toseveral reasons. First, the cost of material to make a usable label 155for the container 100 is reduced. The prior art containers requiredlabels to be adhered to the outer face of the outer wall 120. A portionof the cost to produce the adhesive backed labels is due to the cost ofplacing the adhesive onto the back of the label. With the claimedinvention, adhesive backed labels are not needed. The claimed inventionallows the use of plain-backed labels because the labels are held inplace between the inner wall 105 and the outer wall 120. The cost ofplain-backed labels is lower due to the elimination of the adhesive ofthe back of the label, correspondingly contributing to lowering the costof providing the container 100.

[0045] A second reason the cost in marking or labeling the container 100is reduced is the elimination of time and scrap associated with theplacement of the markings or label on the container 100. The prior artpractice of marking and labeling required the orientation of the markingor labeling with the container so as to provide a pleasing appearance toa person viewing the container. This requires processes for aligning themarking or label with container. These processes produce cosmeticallyunusable containers when these processes do not work correctlyeffectively increasing the per container cost. In contrast, marking ofthe container 100 does not require such orientation processes. Thealignment of the label 155 with the container 100 is accomplished by theedges 160, 165 of the label 155. When the label 155 is placed betweenthe inner wall 105 and the outer wall 120 in the gap 145, the edge 160or 165 is seated against the shoulder 110. When the label 155 seatsagainst the shoulder 110, the label 155 is effectively aligned with theinner wall 105 and outer wall 120 by the profile of the edge 160 or 165.With the use of a standard rectangular label 155 as shown in FIG. 1, thelabel 155 is properly aligned.

[0046] An additional advantage to the labeling of the container 100 inthis manner is allowing users of the container to view the labels 155while the outer wall 120 protects the label 155 from being damagedduring use or handling as shown in FIG. 1. Therefore, the claimedinvention is capable of providing a labeled double walled containerwherein the markings are not susceptible to being damaged.

[0047] A symmetrical bottom plug 200 is shown in FIG. 2 and FIG. 3 thatis sized and shaped to fit within the area enclosed by the outer wallstructure 120. In the illustrated embodiment, the bottom plug 200 isdisc shaped so that it fits within the round configuration of the outerwall structure 120. FIG. 2 shows the bottom plug 200 is designed in asymmetrical manner so that it does not require orientation before beinginserted into the bottom of the container 100, reducing the amount ofassembly time that is required to provide a double walled container 100with a flat bottom surface. The bottom plug 200 has a central lipportion 205 around the side of the bottom plug 200 that snaps into the Vshaped channel 125 within the inner surface of the outer wall structure120 when the bottom plug 200 is inserted into the bottom of thecontainer 100. The bottom plug 200 also has a pair of indexing lugs 210,one on each face of the bottom plug 200, for providing a common point ofreference during printing or other manufacturing operations that may beperformed upon the bottom plug 200.

[0048] The central lip portion 205 design provides a snap-in piece thatis less susceptible to breakage during assembly of the bottom plug 200into the bottom of the container 100. The reduced breakage translatesinto less scrap being made during the assembly process, lowering thecost of the overall jar 10.

[0049] The design of the bottom plug 200 facilitates the construction ofa simplified injection mold as previously mentioned. The bottom plug 200design does not rely on intricate features to function properly.Therefore, the injection mold design is less expensive to initiallyconstruct, and is less expensive to maintain due to reducedsusceptibility to injection mold wear.

[0050]FIG. 1 shows a lid 300 sized and shaped to cover the open top end130 of the inner wall structure 105 can be used to provide a closed jar10. The lid 300 may have threads 305 that are designed to fit in matingrelationship with the set of threads 115 located about the outer surfaceof the inner wall structure 105, or in other embodiments, the lid 300may be configured to fit tightly over the open top end 130 of the innerwall structure 105. The threads 115 and 305 work together with theshoulder portion 110 to provide a fluid tight closure for the jar 10.

[0051] To further achieve the foregoing and other objects of the claimedinvention, a method of making the jar 10 container 100 is also provided.The method comprises molding a single piece double walled container 100using a synthetic plastic by forming an inner wall structure 105 with aclosed bottom end 135 and an outer wall structure 120 while forming theouter wall structure 120 with a terminal end 150 extending past theinner wall structure 105. A V shaped channel 125 is also formed withinthe inner surface of the outer wall structure 120. The inner wall 105and outer wall 120 is left free of any interior obstructions therebetween enabling contents of the container to be clearly visible throughthe inner wall 105 and outer wall 120 structures when the method is usedwith a translucent plastic material. The bottom plug 200 is then molded.The method step comprises molding a bottom plug 200 and sizing andshaping the bottom plug 200 to fit within the area enclosed by the outerwall structure 120 and forming a central lip portion 205 that is sizedand shaped for insertion into the V shaped channel 125. Next, the bottomplug 200 is snapped into the V shaped channel 125. The method stepcomprises inserting the bottom plug 200 into the V shaped channel 125.The bottom plug 200 deflects along the long axis of the bottom plug 200as the bottom plug 200 is pushed into the area encircled by the outerwall structure 125 and returns to original shape upon snapping into theV shaped channel 125.

[0052] In manufacturing a double walled container 100 using this method,many of the problems previously pointed out in the prior art are avoid.The single piece double walled container 100 eliminates the breakagethat was associated with the assembly of two discrete wall structures.The use of a symmetrical bottom plug 200 as shown in FIG. 2 to close offthe bottom of the container 100 reduces the assembly time that isrequired to supply a finished double walled container 100. In theclaimed method, the assembly step of orientating the bottom plug 200with respect to the container 100 is greatly reduced or eliminated dueto the symmetrical nature of the bottom plug 200. Since the bottom plug200 is symmetrical, the bottom plug 200 can not be snapped into thebottom of the container 100 in an incorrect orientation. This method ofmanufacture is also advantageous in that the overall cycle time it takesto mold the container 100 and the bottom plug 200 is less than that ofthe prior art using two discrete containers used in nested relationship.A further advantage of this method is the reduced tooling cost in makinga mold to produce the bottom plug 200.

[0053] The invention described above is the preferred embodiment of thepresent invention. It is not intended that the novel device be limitedthereby. The preferred embodiment may be susceptible to modificationsand variations that are within the scope and fair meaning of theaccompanying claims and drawings.

I claim:
 1. A double walled jar, the jar comprising: a single piecedouble walled container, the container comprising: an inner wallstructure having an open top end and a closed bottom end; an outer wallstructure having a proximal end and a terminal end encircling the innerwall structure forming a gap between the inner wall structure and theouter wall structure, the gap between the inner wall structure and theouter wall structure being greater near the terminal end of the outerwall structure than near the proximal end of the outer wall structure,the terminal end extending past the closed bottom of the inner wallstructure and having a notched channel within the inner surface of theouter wall structure located below the closed bottom of the inner wallstructure; a shoulder portion linking the inner wall structure with theouter wall structure extending continuously from and about the outersurface of the inner wall structure to the proximal end of the outerwall structure, the shoulder portion being the sole means of linking theinner wall structure and the outer wall structure; a set of threadslocated above the shoulder portion and about the outer surface of theinner wall structure; a bottom plug sized and shaped to fit within thearea encircled by the outer wall structure having a portion sized andshaped for a snap fit into the notched channel within the inner surfaceof the outer wall structure; and a lid sized and shaped to cover theopen top end of the inner wall structure, the lid having a set ofthreads formed to fit in mating relationship with the set of threadslocated about the outer surface of the inner wall structure.
 2. The jarof claim 1 wherein the notched channel is located within the innersurface of the outer wall structure such that a face of the bottom plugcomes into contact with the closed bottom end when the bottom plug issnapped into the notched channel, the closed bottom providing support tothe bottom plug.
 3. The jar of claim 2 wherein the thickness of theouter wall structure and the thickness of the bottom plug have arelationship such that the bottom plug deflects along the long axis ofthe bottom plug as the bottom plug is pushed into the area encircled bythe outer wall structure and returns to is original shape when thebottom plug snaps into the notched channel.
 4. The jar of claim 3further comprising a label placed in the gap between the inner wallstructure and outer wall structure, the label held in place by the innerwall structure, outer wall structure and bottom plug.
 5. The jar ofclaim 4 wherein the shoulder portion is a fluid tight seat for the lidwhen the lid is secured to the container.
 6. The jar of claim 5 whereinthe bottom plug is symmetrical about the long axis of the bottom plug.7. The jar of claim 6 wherein the thickness of the inner wall structureis from about 0.035 inches to about 0.047 inches and the thickness ofthe outer wall structure is less than the thickness of the inner wallstructure.
 8. The jar of claim 7 wherein the bottom plug has at leastone indexing lug providing a common point of reference for performingmanufacturing processes on the bottom plug.
 9. A single piece doublewalled container in combination with a symmetrical bottom plug, thecombination comprising: a single piece double walled container having aninner wall structure with an open top end and a closed bottom end; anouter wall structure having a proximal end and a terminal end encirclingthe inner wall structure forming a gap between the inner wall structureand the outer wall structure, the terminal end of the outer wallstructure extending past the closed bottom of the inner wall structureand having a notched channel within the inner surface of the outer wallstructure located below the closed bottom of the inner wall structure; ashoulder portion linking the inner wall structure with the outer wallstructure extending continuously from and about the outer surface of theinner wall structure to the proximal end of the outer wall structure,the shoulder portion being the sole means of linking the inner wallstructure and the outer wall structure; and a symmetrical bottom plughaving a portion sized and shaped for insertion into the notched channelwithin the inner surface of the outer wall structure.
 10. Thecombination of claim 9 wherein the notched channel is located within theinner surface of the outer wall structure such that a face of the bottomplug comes into contact with the closed bottom end when the bottom plugis inserted into the notched channel, the closed bottom end providingsupport to the bottom plug.
 11. The combination of claim 10 wherein thegap between the inner wall structure and the outer wall structure beinggreater near the terminal end of the outer wall structure than near theproximal end of the outer wall structure
 12. The combination of claim 11further comprising a label placed in the gap between the inner wallstructure and outer wall structure, the label held in place by the innerwall structure, outer wall structure and bottom plug.
 13. Thecombination of claim 12 further comprising a set of threads locatedabove the shoulder portion and about the outer surface of the inner wallstructure.
 14. The combination of claim 13 further comprising a lidsized and shaped to cover the open top end of the inner wall structure,the lid having a set threads formed to fit in mating relationship withthe set of threads located about the outer surface of the inner wallstructure.
 15. The combination of claim 14 wherein the shoulder portionis a fluid tight seat for the lid when the lid is secured to thecontainer.
 16. In a double walled injection molded plastic containerhaving a gap between the inner wall and the outer wall, the improvementcomprising: forming the inner wall and outer wall out of one continuouspiece of injection molded plastic; extending the outer wall past thebottom of the container; forming a notched channel within the innersurface of the outer wall located below the bottom of the container; andinserting a bottom plug having a portion sized and shaped for a snap fitinto the notched channel.
 17. The improved container of claim 16 whereinthe thickness of the inner wall is from about 0.035 inches to about0.047 inches and the thickness of the outer wall is less than thethickness of the inner wall.
 18. The improved container of claim 17wherein the bottom plug is symmetrical about the long axis of the bottomplug.
 19. The improved container of claim 18 further comprising at leastone indexing lug providing a common point of reference for performingmanufacturing process on the bottom plug.
 20. A method of manufacturinga single piece double walled container, the method comprising: molding asingle piece double walled container using a translucent syntheticplastic by forming a translucent inner wall structure with a closedbottom end and a translucent outer wall structure while forming theouter wall structure with a terminal end extending past the inner wallstructure and a notched channel within the inner surface of the outerwall structure, the inner and outer translucent wall structure beingleft free of any interior obstructions there between enabling contentsof the container to be clearly visible through the translucent inner andouter wall structures; molding a bottom plug and sizing and shaping thebottom plug to fit within the area enclosed by the outer wall structureand forming a portion that is sized and shaped for insertion into thenotched channel; and inserting the bottom plug into the notched channel,the bottom plug deflecting along the long axis of the bottom plug as thebottom plug is pushed into the area encircled by the outer wallstructure and returning to original shape upon seating into the notchedchannel.
 21. The method of manufacturing of claim 20 wherein the moldingof the bottom plug further comprises symmetrically forming the bottomplug about the long axis of the bottom plug.
 22. A single piece doublewalled container of translucent plastic providing unobstructed view ofthe contents of the container, the container comprising: an inner wallstructure having an open top end and a closed bottom end; an outer wallstructure having a proximal end and a terminal end encircling the innerwall structure forming a gap between the inner wall structure and theouter wall structure; and a shoulder portion linking the inner wallstructure with the outer wall structure extending continuously from andabout the outer surface of the inner wall structure to the proximal endof the outer wall structure such that the viewing of the contentsthrough the outer wall structure and the inner wall structure of thecontainer is unobstructed.
 23. The single piece double walled containerof claim 22 wherein the shoulder portion is the sole means of linkingthe inner wall structure and the outer wall structure.
 24. The singlepiece double walled container of claim 23 wherein the shoulder portionis a fluid tight seat for a lid when the lid is placed on the container.25. The single piece double walled container of claim 24 wherein theouter wall structure extends past the closed bottom of the inner wallstructure and further comprises a notched channel within the innersurface of the outer wall structure located below the closed bottom ofthe inner wall structure.
 26. The single piece double walled containerof claim 25 further comprising a bottom plug sized and shaped to fitwithin the area encircled by the outer wall structure having a portionsized and shaped for a snap fit into the notched channel within theinner surface of the outer wall structure.
 27. The single piece doublewalled container of claim 26 further comprising a set of threads locatedabove the shoulder portion and about the outer surface of the inner wallstructure.
 28. The single piece double walled container of claim 27further comprising a label placed in the gap between the inner wallstructure and outer wall structure, the label held in place by the innerwall structure, outer wall structure and bottom plug.
 29. A labeleddouble walled jar of translucent plastic, the jar comprising: an innerwall structure having an open top end and a closed bottom end; an outerwall structure having a proximal end and a terminal end encircling theinner wall structure forming a gap between the inner wall structure andthe outer wall structure the terminal end extending past the closedbottom of the inner wall structure and having a notched channel withinthe inner surface of the outer wall structure located below the closedbottom of the inner wall structure; a shoulder portion linking the innerwall structure with the outer wall structure extending continuously fromand about the outer surface of the inner wall structure to the proximalend of the outer wall structure; a bottom plug sized and shaped to fitwithin the area encircled by the outer wall structure having a portionsized and shaped for a snap fit into the notched channel within theinner surface of the outer wall structure; and a label placed in the gapbetween the inner wall structure and outer wall structure, the labelheld in place by the inner wall structure, outer wall structure andbottom plug.
 30. The labeled double walled jar of claim 29 wherein thenotched channel is located within the inner surface of the outer wallstructure such that a face of the bottom plug comes into contact withthe closed bottom end when the bottom plug is snapped into the notchedchannel, the closed bottom providing support to the bottom plug.
 31. Thelabeled double walled jar of claim 30 wherein the thickness of the outerwall structure and the thickness of the bottom plug have a relationshipsuch that the bottom plug deflects along the long axis of the bottomplug as the bottom plug is pushed into the area encircled by the outerwall structure and returns to is original shape when the bottom plugsnaps into the notched channel.
 32. The labeled double walled jar ofclaim 31 wherein the shoulder portion is a fluid tight seat for the lidwhen the lid is secured to the container.
 33. The labeled double walledjar of claim 32 wherein the bottom plug is symmetrical about the longaxis of the bottom plug.
 34. The labeled double walled jar of claim 33wherein the thickness of the inner wall structure is from about 0.035inches to about 0.047 inches and the thickness of the outer wallstructure is less than the thickness of the inner wall structure. 35.The labeled double walled jar of claim 34 wherein the bottom plug has atleast one indexing lug providing a common point of reference forperforming manufacturing processes on the bottom plug.